Fluid heating furnace with rotary combustion and heat exchange casing



2 Sheets-Sheet 1 INVENTOR.

Feb. 5, 1957 Filed me 15, 1953 R. R. WITHERELL 2,780,217 FLUID HEATINGFURNACE WITH ROTARY COMBUSTION AND HEAT EXCHANGE CASING I 2 Sheets-Sheet2 Feb. 5, 1957 Filed June 15, 1953 :FLUID HEATING FURNACE WITH ROTARYCOM- BUSTION AND HEAT EXCHANGE CASING Robert R. Witherell, Bloomington,111., assignor, by mesne assignments, to Eureka 'Williams Corporation, acorporation of New York Application June 15,1)53, Serial No. 361,680

SClaims. ((31. 126-110) This invent-ion relates to heating apparatus andin the form disclosed has particular'reference to furnaces.

My invention contemplates a heating apparatus which comprises in generala rotatable-hollow heat exchanger casing which forms the outer wall of acombustion chamber, the combustion changer having associated therewithfuel supply means operable for discharging a combustible-fluid mixtureinto said chamber for combustion therein, means for rotating said casingat such a speed as to eifect the flow of the products of combustiongeneratedin said chamberin intimate heat exchange relation with theconfining walls of the chamber, the outer surface of the casing beingexposed to and in contact with fluid to be heated, and meansrotatablewith said casing for withdrawing the products .of combustion therefromafter the major portion of the heat of said products of combustion hasbeen transferred to said casing. v

The rotation of the heat exchanger casing in effect greatly increasesthe heat transfer surface or capacity thereof and. in additionsubstantially increases the efficiency of the heat transfer betweentheproducts of combustion and the fluid to .beheated whereby it ispossible by utilizing my invention to build heating apparatus of muchless mass and size for a given capacity as compared with conventionalapparatus.

A principal object of the invention, therefore, is to provide a new andimproved heating apparatus. I

Another object of the invention is to provide a new and improvedfurnace.

Other and further objects of theinvention will be apparent from thefollowing description and claims and may be understood by reference tothe accompanying drawings,- of which there are two sheets, which by wayof illustration show a preferred embodiment of my invention and what Inow consider to be the best mode of applying the same.

In the drawings:

Fig. 1 is a vertical sectional view ofa furnace embodying the invention,certain parts being illustrated schematically;

Fig. 2 is a fragmentary sectional view with certain of the parts beingshown in elevation; and

Fig. 3 is a cross section taken generally along the line 3-3 of Fig. 1.

As illustrated in the embodiment of the invention selected for purposesof illustration, a heating apparatus embodying my invention comprises ingeneral a rotary hollow heat exchanger casing forming the outer walls ofa combustion chamber 12, fuel supply means 14 operable for discharging acombustible fluid mixture into the chamber 12 for combustion therein, amotor '16 drivingly connected to said casing and operable for rotatingthe same at such a speed as to effect the flow of the products ofcombustion generated in the chamber 12 in intimate heat exchangerelation with the walls of said casing 10, means including a suction fan18 carried by and rotatable with the casing 10 and operable uponrotation thereof for reducing the pressure in said combustion chamber2,780,217 Patented 1 Feb. 5, 1957 -supply'mcans 14 may comprise anyconventional or suitable oil orgas burner, but'prefe'rably I contemplateemploying a'power operated low pressure type of oil burner according tothe construction'disclosed' in my prior application, SerialNumber3l0,961, filed-September23, 1952, for Oil Burner, and assigned tothe assignee of the present application. Insofar. as this invention.iscGncerned, such an oil burner includes an oil and air mixing nozzlearranged adjacentvthe discharge end of a secondary air supply tube 32,the nozzle and tube 32 being arranged to discharge into the combustionchamber12. The nozzle -30-c0mprises an oil and air mixing nozzlewhic'his constructed and arrangedso as to mix oil and air suppliedthereto-and to discharge'such mixture of oil and airin'the form'of aspray of air and finely divided oil particles into a stream-of secondaryair supplied through the tube 32 st) as toform :acombustible mixturetherewith and tsuchcombustible mixture is discharged into the chamber 12and isignited by the electrodes 34 of an ignition system. 30

generally spherical portion.36' and a tubular neck or The heatrexchanger casingll) as illustrated comprises a portionBS. Abearing 40 carriedbya frame 42 rot'atably supports the neck 38. A hollow spindle 44affixed to the spherical port-ion 36is journalled in a bearing andsealassembly 46 carried by the end wall 48 of the casing. A disc-shapedbaflle 50 carried by and rotatable with the spindle v44 serves as a heatshield for the bearing46. The interior of the spindle 44 may serve as ameans for introducing additional secondary air into the chamber 12 andthe air so supplied'will help to cool the bearing assembly 46. A pulley52 afiixed to the spindle 44 for rotation therewith is driven from themotor pulley 54- by abelt 56.

The annual passage 55 formed between the outside of the tube 32 and theinside of the neck 38 forms a discharge passage from the combustionchamber 12 for the products of combustion. The neck 38 is provided witha seriesof apertures 60 which communicate with the inside of thecentrifugal fan 18, the blades 62 of which are aifixed to the neck 38for rotation therewith. The fan casing 64 is provided with a dischargepipe 67 which may be connected to a smoke pipe(not shown) for ventingthe products of combustion. A stationary deflecting baffle 66 may bearranged on the outside of the tube 32 so as to deflect the flow of theproducts of combustion through the apertures 60.

The heat exchanger 10 preferably is enclosed in a stationary shroud 68which cooperates with the outer surface of the exchanger 10 to define apath 70 for the flow of air to be heated in intimate heat exchangerelation with the heated surface of the casing 10. The path 70 'at-oneend opens into the inlet chamber 72 of the furnace so as to be suppliedwith air therefrom and at its other end discharges into the chamber 74which in turn communicates with the outlet 26. A partition 76 extendsbetween the exterior of the shroud 68 and the walls of the outer casing22 so as to separate the intake side of the furnace from the dischargeside thereof. The shroud 68 is supported at one end by the partition 76and at itsother end by spaced brackets 77.

The fan20 as illustrated comprises a series of blades 78 fixed to theneck 38 for rotation therewith and disposed adjacent the intake end ofthe shroud 68. Upon rotation of the casing 10 the fan 20 is operable topump air to be heated thropgh the passage 70 and through the ducts ofthe system with which the furnace may be connected. The fan casing 64 issupported by. struts 80 carried by the shroud 68, the struts 80 beinglocated in the path 70 and may be utilized as vanes to deflect the airdischarged by the fan 20 along the path 70. Additional vanes 82 may alsobe employed for such purpose, if necesssary. Suitable sealing provisionsare made between the stationary fan casing 64 and the rotating neck 38which extends through the center thereof.

In operation the combustible mixture supplied to the chamber 12 isignited and burned therein to generate highly heated products ofcombustion. The rotation of the exchanger 10 will impart a rotary motionto the combustible mixture and the flame and this serves to promote thecombustion of such mixture by increasing the rate of flame propagation.In addition the rotation of the casing 10 also serves to cause theheated product of combustion to ffow under the influence of centrifugalforce in intimate heat exchange relation with the inner surface of thecasing 10, thus creating turbulence in such products of combustion andeffecting a scrubbing action between such products of combustion and theconfining wallls of the casing 10. The interior of the casing 10 may beprovided with a series of bafiles 84, if desired, to increase thisaction and also to assist in directing the fiow of products ofcombustion into the discharge passage 55. The motor 16 is arranged torotate the casing 10 at such speed as to effect the flow of the productsof combustion into intimate heat exchange relation with the confiningwalls of the chamber 12 and to effect the foregoing actions in the mosteffective manner. Naturally, the speed of rotation of the casing 10 willdepend to some extent on the size of it with relation to the rate atwhich fuel is being burned therein and I contemplate that in a furnaceof the size illustrated where the chamber 12 is approximately 12 inchesin diameter, that the casing 10 would be rotated at the speed of theorder of 500 R. P. M. when burning oil at the rate of A of a gallon perhour. The operation of the suction fan 18 upon the rotation of thecasing 10 will reduce the pressure in the combustion chamber 12 so as toexpedite the withdrawal of the products of combustion therefrom. Theoperation of the fan 20 with the rotation of the casing 10 will serve toeffect the flow of air to be heated in intimate exchange relationshipwith the heated walls of the casing 10 and the rotation of the casing 10will tend to cause the air in the path 70 to rotate in a spiral path,thus effectively increasing the length of travel of the air in contactwith the casing 10. In addition, the rotation of the casing 10 willeffect a certain amount of turbulence of the air in the path 70 and agood wiping action between the air in the path 70 and the casing 10 soas to increase the dissipation of heat from the casing 10. It willfurther be noted that the secondary air supplied under pressure throughthe tube 32 flows in heat exchange relation with the products ofcombustion in the path 55 which will have the effect of increasing theefiiciency of combustion of the fuel in the chamber 12.

While I have illustrated and described a preferrred embodiment of myinvention, it is understood that this is capable of modification and Itherefore do not wish to be limited to the precise details set forth butdesire to avail myself of such changes and alterations as fall withinthe purview of the following claims.

I claim:

1. Heating apparatus comprising a rotatable hollow heat exchanger casinghaving a portion forming a combustion chamber and an elongated neckportion communicating therewith, fuel and air supply means projectiuginto said casing through said neck portion and operable to discharge acombustible mixture of fuel and air into said combustion chamber, meansfor rotating said casing about the axis of said neck portion at suchspeed as to bring the products of combustion of said mixture intointimate heat exchange relation with the walls of said heat exchanger,said neck portion having means for the discharge of products ofcombustion from said combustion chamber, means carried by and rotatablewith said casing and operable upon rotation thereof for effecting theflow of said products of combustion from said chamber through said neckportion and said discharge means, and means for effecting the flow offluid to be heated in heat exchange relation with the outer surface ofsaid casing.

2. Heating apparatus according to claim 1 wherein said supply meansincludes an air supply tube disposed within said neck portion of saidcasing and adapted to supply air for combustion in heat exchangerelation with the products of combustion being discharged from said neckportion.

3. Heating apparatus according to claim 1 wherein said means to effectthe flow of fluid to be heated comprises a blower mounted on theexterior of said casing for rotation therewith.

4. Heating apparatus comprising an elongated rotatable hollow heatexchanger casing of circular cross-section forming a combustion chamber,fuel and air supply means including an air supply tube projecting intosaid casing in spaced relation therewith through one end thereof andoperable to discharge a combustible mixture of fuel and air into saidcombustion chamber, bearing means rotatably supporting said one end ofsaid casing, means drivingly connected to the other end of said casingfor rotating said casing about its axis to bring the products ofcombustion of said mixture into intimate heat exchange relation with theinner surface of said casing, said one end of said casing having meansfor the discharge of products of combustion from said combustionchamber, means carried by and rotatable with said casing and operableupon rotation thereof for effecting the flow of said products ofcombustion from said chamber through said discharge means, said airsupply tube projecting inwardly of said casing beyond said dischargemeans whereby air for combustion is supplied by said tube in heatexchange relation with said products of combustion, a shroud surroundingsaid casing in spaced relation and defining an annular path therewithfor the flow of fluid to be heated, and means carried by and rotatablewith said casing and operable upon rotation thereof for effecting theflow of fluid to be heated through said path in heat exchange relationwith the outer surface of said casing.

5. Heating apparatus comprising a rotatable hollow heat exchanger casingforming the outer walls of a combustion chamber, said casing having asubstantially spherical portion and an elongated neck portioncommunicating therewith, fuel and air supply means projecting into saidcasing through said neck portion and operable to discharge a combustiblemixture of fuel and air into said combustion chamber, means for rotatingsaid casing about the axis of said neck portion at such speed as tobring the products of combustion of said mixture into intimate heatexchange relation with the walls of said heat exchanger, said neckportion having means for the discharge of products of combustion fromsaid combustion chamber, means carried by and rotatable with said casingand operable upon rotation thereof for effecting the flow of saidproducts of combustion from said chamber through said discharge means, ashroud surrounding said casing in spaced relation and defining anannular path therewith for the flow of fluid to be heated, and meanscarried by and rotatable with said casing and operable upon rotationthereof for effecting the flow to be heated through said path in heatexchange relation with the outer surface of said casing.

(References on following page) References Cited in the file of thispatent 2,414,829 McCollum 9 I an. 28, 194

UNITED STATES PATENTS 2,414,830 MCCOllUm Jan. 28, 1 4' 2263998 MFCOHUm1941 5 2:590:109 Lindenbaum Mar. 25 1951 2,354,345 Wmtergreen -July 25,1944

